Convertible skimming boat or like water craft



. April 3, 1928.

' P. H. VAN WIENEN CONVERTIBLE SKIMMING BOAT 0R LIKE WATER CRAFT Filed July 16 1926 Patented Apr. 3, i928.

co mune SVKIMMINGIBOAT on LIKE. WATER mam,-

PIETER HENDRIX VAN winnnn orna unune, GERMANY v Application filed July 1s, 1326, Serial No. 22,990, and iiiGermany September 23,1925,

.For the purpose of reducing the water displacement and for utilizing the driving power use has been made for some consider able time of the so-called skimming boats or I5 boats of the hydroplane type having stepped bottoms. All the knownconstructions, how- 'ever, have not so far satisfied the demand fully and have been found totally inefiicient particularly in shallow seas with sand banks 1 or during heavy weather.

- occurrence of heavy weather the pilot became even exposed to the risk of losing both .boat and life.

I With a view to overcoming the above diss advantages according ,to this invention the craft is so constructed asl to enable it to be peed both as a skimmingand ordinary water oat. l

To this end the bottom of the boat is provided with a recess or recesses for the. ac-

commodation of wedge-shaped 7 members adapted to be rotated about horizontal transverse axes whereby steps may be formed on the bottom of the 'bo'atvby vthe swinging out of these members.

In'calm weather the craft may be used even in a relatively large size as a skimmmg --bat without risk of losing her stability.

The wide portion of the wedge-shaped member is then lowered down to project into the water. On the occurrence of: sudden heavy weather the wedge-shaped member or members' may be drawn in recess provided therefor. The boat is then able to sinkto a lower depth and then operates purely as an ordinary'water craft.

My invention is illustrated diagrammatically and byway of example on the accompanying drawings in which Figure 1 is a side-view of a combined skimming and stepped boat designed according to this invention, Figure 2 a vertical cross-section on the line'Ar-B of Fig. 1,Figure 3 a similar section on the line C-D and Figure 4 is a section on the line E-'-F of Fig. 1; and Figure 5v through aportion of the bottom of the boat drawn to an enlarged scale and showing one constructional form of the wedge-shaped .member. r

The'bow a of the boat is of the V' type. The keel b is constructed to assume a drop shaped form towards the centre and the bottom of the craft has the form of a shallow arch on both sides towards the sterne Ad jacent to the inid'ship keel b are On the sudden.

fates as an ordinary to lodge within the the front end of the is a vertical longitudinal section cillable about'atransverse pin i.

on each sidein' proxlmityto the .midship keel. The' wedge-shaped members 9 maybe raised andflowered by mea of s- 0 through the agen f tion the wedge-shaped member acts as a lifting body raising the bow of the'crait out of j the water to H adapt the latter 'for calm weather to travel as a fast skimmer-or surface boat. When the wedge-shaped member 'is withdrawn its lower face lies flush'with The boat then oper- 7 5 the bottom of the boat.

displacement craft capable of being used as a heavy weather craft. The arrangement may be made use of also in the event of a flat keel construction.

In this case the recess extends over them whole breadth of the keel and only one wedge-shaped member need be built into the cavity. j l The wedge-shaped member 9 is provided with a sharp front end 1 and a rear blunt end 2 and the member is pivoted intermediate its ends at the point 3 asjclearly shown in Fig. 5.. I

I claim:

boat comprising'a keel and a bottom portion having a recess therein; anda wedgeshaped member pivoted intermediate its ends in the recessandhaving a front sharp end and a rear blunt end, said member when entirely in the recess bottom with the bottom of the boat to render the boat a displacement boat and when the rear. blunt end projects beyond the recess blunt end of the member form projecting steps in the bottom of the boat to. render the boat a surface boat.

2. A combined surface and displacement boat comprising a keel and a bottom portion having a recess therein; a wedge-shaped member pivoted intermediate its ends in the recess and having a front sharp end and a rear blunt end, said member when'entirely inlthe recess presenting a smooth bottom yvith the bottom of the boat to render the cat a a. worm gear g. 65 When the rear portion of eachwedge-shaped member is lowered into thefwater its rear face 7" produces a second step; In this posi- W 1. A combined surfaceand displacement .90

presenting a smooth v recess and the reardisplacement boat and when the rear in the bottom of the boat -to render the.

blunt end projects beyond the recess the front end of the recess and the rear blunt end of'the member form projecting steps boat'a surface boat; and means, for raising and lowering the ends of the member. 3. Avcomblned'snrfaceand displacement boat comprising a keel :and a bottom portion having a recess therein; and a two-armed and. edge-shapedmember pivoted intermediateits, ends in the recess, said memberwhen entirely fin the recess presenting a i smooth bottom with the bottom of the boat to render the boat a-jdisplacement'boatand when one end of thememberprojects beyond the recess a pair of steps will gb formed in. the bottom of the; boat to render i the boat a. surface boat. r Y

4. A combined surface and displacement boat comprising a keel and a bottom portion havingia recess therein; and a twoar'med and Wedge-shaped member pivoted intermediate its ends in the recess, saidmember' when entirely 1n the r-ecess presentmg a. smooth bottom with the bottom of the boatto render the: boat a displacement boat and When one end of the, member projects beyond the recess a step Will be formed at the front end of the recess and a step Will be formed at the rearf.e11d of the Wedgeshaped member to form a pair of steps in 1 the bottom of the boat to render the boat a surface boat.

5. A combined surface anddisplacement boat comprising a keel and a bottom upo'rtron having a recess thereln; a two-armed and wedge shaped 7 member pivoted intermedilate its ends 1n the recess,-sa1d member when entirely mtheirecess presentinga smooth bottom With'the bottom" of the boat to render the boat adisplacement boat and 7 When one end of the member projects bed the recess a step ill be formed at I p the; front end of the recess anda step, will be formed at the rear end of the Wedgeshapedomember to form a pair of steps in 

